System, apparatus, and methods are disclosed for treating a reduction catalyst that has been exposed to an amount of sulfur. The treating of the reduction catalyst includes providing a fluid stream at a position upstream of the reduction catalyst. The fluid stream includes a temperature and a reductant amount, and the reductant amount includes an amount of urea, ammonia, or hydrocarbons.

System, apparatus, and methods are disclosed for treating a reduction catalyst that has been exposed to an amount of sulfur. The treating of the reduction catalyst includes providing a fluid stream at a position upstream of the reduction catalyst. The fluid stream includes a temperature and a reductant amount, and the reductant amount includes an amount of urea, ammonia, or hydrocarbons.

A process for activating a hydroalkylation catalyst in a first state comprising an acid component and a hydrogenating metal component, including: (i) treatment at a temperature of at least 120 C. in the presence of hydrogen for a first duration to produce a catalyst in a second state having a first hydroalkylation activity; (ii) contacting the catalyst in the second state with an aromatic compound and hydrogen under a hydroalkylation condition effective to convert at least part of the aromatic compound to a cycloalkylaromatic compound and produce a catalyst in a third state; and (iii) treating the catalyst in the third state at a temperature of at least 160 C. in the presence of hydrogen but advantageously in the substantial absence of the aromatic compound for a third duration to produce an activated catalyst in a fourth state having a third hydroalkylation activity greater than the first hydroalkylation activity.

A process for activating a hydroalkylation catalyst in a first state comprising an acid component and a hydrogenating metal component, including: (i) treatment at a temperature of at least 120 C. in the presence of hydrogen for a first duration to produce a catalyst in a second state having a first hydroalkylation activity; (ii) contacting the catalyst in the second state with an aromatic compound and hydrogen under a hydroalkylation condition effective to convert at least part of the aromatic compound to a cycloalkylaromatic compound and produce a catalyst in a third state; and (iii) treating the catalyst in the third state at a temperature of at least 160 C. in the presence of hydrogen but advantageously in the substantial absence of the aromatic compound for a third duration to produce an activated catalyst in a fourth state having a third hydroalkylation activity greater than the first hydroalkylation activity.

Disclosed are a catalyst pre-hydrocarbon-pooling method and a pre-hydrocarbon-pooling device, relating to the technical field of preparation of low carbon olefins. A regenerated catalyst enters a pre-hydrocarbon-pooling reactor, and a pre-hydrocarbon-pooling reaction occurs between the regenerated catalyst and an activation medium to form hydrocarbon pool active species. Pre-hydrocarbon-pooling treatment is performed on the regenerated catalyst by providing a pre-hydrocarbon-pooling device, so that the regenerated catalyst forms the hydrocarbon pooled active species and carbon deposition before entering into an oxygenate conversion reactor, by way of which hydrocarbon pool active species distribution and coke distribution of the catalyst in the conversion reactor are improved. This shortens or eliminates a reaction induction period and improves the catalytic activity and selectivity of the regenerated catalyst for a reaction of an oxygenate to low-carbon olefins.

Disclosed are a catalyst pre-hydrocarbon-pooling method and a pre-hydrocarbon-pooling device, relating to the technical field of preparation of low carbon olefins. A regenerated catalyst enters a pre-hydrocarbon-pooling reactor, and a pre-hydrocarbon-pooling reaction occurs between the regenerated catalyst and an activation medium to form hydrocarbon pool active species. Pre-hydrocarbon-pooling treatment is performed on the regenerated catalyst by providing a pre-hydrocarbon-pooling device, so that the regenerated catalyst forms the hydrocarbon pooled active species and carbon deposition before entering into an oxygenate conversion reactor, by way of which hydrocarbon pool active species distribution and coke distribution of the catalyst in the conversion reactor are improved. This shortens or eliminates a reaction induction period and improves the catalytic activity and selectivity of the regenerated catalyst for a reaction of an oxygenate to low-carbon olefins.

Methods of treating hydroconversion catalysts used for cracking of hydrocarbons are described. A method can include mixing an inactive hydroconversion catalyst with a solid hydrocarbon containing material having a melting point of 50 C. or greater. The inactive hydroconversion catalyst/solid hydrocarbon containing material mixture can be contacted with a gaseous stream that includes hydrogen (H.sub.2) and a sulfur-containing compound under conditions sufficient to sulfide the catalyst and carbonize at least a portion of the hydrocarbon containing material on the sulfided catalyst to obtain a treated sulfided hydroconversion catalyst.

Methods of treating hydroconversion catalysts used for cracking of hydrocarbons are described. A method can include mixing an inactive hydroconversion catalyst with a solid hydrocarbon containing material having a melting point of 50 C. or greater. The inactive hydroconversion catalyst/solid hydrocarbon containing material mixture can be contacted with a gaseous stream that includes hydrogen (H.sub.2) and a sulfur-containing compound under conditions sufficient to sulfide the catalyst and carbonize at least a portion of the hydrocarbon containing material on the sulfided catalyst to obtain a treated sulfided hydroconversion catalyst.